Chables l



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G. L. BELLAMY.

MANUFACTURE OF KNIFE BLADES.

Patented June 9-, 1885.

N, PETERS, PhowLilhogmpher. Washington a. c.

Jur /26 01 ra'rrts CHARLES L.

BELLAMY, OF ARLINGTON, NEW JERSEY.

ilDl-ZGIFIGATIGN forming part of Letters Patent No. 319,442, dated June 9, 1885.

Application filed April 25, 1884. (No model.)

To all whom it may concern:

Be it known that I, OHARLns L. BELLAMY, of Arlington, Hudson county, New Jersey, have invented certain new and useful Improvements in the Manufacture of Knife- Blades, of which the following is a specification.

My invention relates more especially to the manufacture of blades for ordinary tableknives, but may, of course, be applied to the manufacture of blades for other cutlery.

The main object of my invention is to enable knife-blades to be rapidly and cheaply made from sheet-steel in a perfect form without the necessity of the expensive hand forging of each blade, as is' now employed in the manufacture of properly-formed blades.

It is well known that it is considered an essential that all properly-formed knife-blades should have atapering or wedging cross-sec tion, tapering from the back to the edge, and that heretofore this has been obtained only by the operation of forging or by grinding, the former being expensive in labor, and the latter wasteful of material. Ithas therefore been often sought to obtain steel rolled in long thin strips with a wedging cross-section suitable to knife-blades, whereby the blades may be readily produced by cutting off sections of the bar and finishing these sections; but the difiiculty or impossibility of producing bars in this shape which would be straight and not curled up has rendered this idea impracticable. According to my invention, however, I produce knife-blades of true wedging form from sheet-steel by the simple operations of cutting and rolling, without appreciable waste of material and without the necessity of expensive forging; and this result I accomplish by first cutting the blade-blank from a sheet of steel of proper width and thickness in a curved or curled form, and then passing this curved piece between beveled rollers, or rather rolls with grooves of a wedging shape, which rollers roll the strip thin or displace the metal on the concave side of the curved strip, thus stretching the metal sufficiently on that side to neutralize the curves and thus straighten the curved strip at the same time that it forms it with a wedging cross-section; and my invention consists, mainly, in the features here outlined, as hereinafter fully set forth.

In the drawings annexed, Figure 1 presents the rollers, and Fig. 6 is a cross-section thereof.

Referring to Figs. 1 and 2, a indicates the blade-blank as it is cut from the sheet of steel, and 2) indicates the sheet from which the blanks are cut. and of uniform thickness, as shown, and of a width equal to the length of the blanks. The blanks, as shown, are out in a curved form, the convex curved side corresponding to the back edge of the finished blade,while the concave side corresponds to the cutting-side of the blade, and these curves have a definite relation or proportion to the width of the blank, its thickness of metal,and the wedging form of the finished blade, so that when the The steel sheet bis flat I blank is rolled and the concave edge thinned course vary for different sizes and kinds of blades, and no specific directions for laying out the curves are therefore given here, as it is the function of the experienced metal worker to determine this in each case. I prefer, however, to have the concave and convex curves of the blade parallel, as shown, so that the blanks can therefore be cut transversely from the sheet 6 in direct succession without Waste, as indicated by dotted lines in Fig. 2.

The blanks, as shown best in Fig. 1, are cut with a narrow tongue, 0, at one end, which forms the tang of the finished blade, and the small pieces cut from the blank on each side of this tang (see the dotted lines in Fig. 2) form the only waste in the operation of cutting, as will be readily understood.

The blanks when out, as seen in Fig. l, are of course of uniform thickness, as shown in Fig. 8, and they are then passed through the rollers cl d, (shown in Fig. 4,) which reduces the thickness on one side. These rollers are formed with wideand jshallow beveled or inclined grooves ff, the coincidence of which presentan opening of wedging form, as illustrated, corresponding to the cross-section of the knife-blade, as seen in Fig. 6, and the grooves are so proportioned to the blank that the area of the said wedging opening is about equal to the cross-section of the blade-blank, as seen in Fig. 3.

The rollers d d are of course mounted and operated in the same manner as rollers gentaperingor wedging form in cross-section, as

' seen in Fig. 6, while the top end of the blade will be pointed, as seen in Fig. 5, thus producing from sheet-steel, without waste and without forging, ablade-blank of proper wedging form, which is an important improvement in the manufacture of knife-blades. This rolling operation may be performed while the blanks are heated to a cherry red, if desired,

but it can be performed with perfect success with the blanks cold, which is a most important advantage of this system, and will avoid a the expense of heating and the scale which results therefrom, and enable the blades to be finished more readily.

After the blanks are rolled, as in Fig. 5,

- they are finished by grinding the top of the blade to the proper shape, and also grinding or filing the tang end of the blade to properly,

fitthe blade to the handle, after which the blanks are tempered, and after the tempering the cutting-edge of the blade is ground or.

sharpened to the desired acuteness, and the blades are finally polished, and are then finished and ready to be attached to the handles, thus rendering the manufacture of the blades very simple and rapid from the first operation to the last, and of such a nature that it may all be performed by machinery without skilled labor, thereby rendering my invention a valuable improvement in the manufacture of cutlery,

It will bereadily noted that as the metal is compactly rolled along the thin or cutting edge of the blade, the finished blade will possess a cutting-edge of much better quality than usual, on account of the density and strength of metal therein, which will enable the blade to take a much keener edge than usual, and

at first in a curved form, and hence I do not wish to limit myself to this operation, as it may be possible to cut the blanks straight, and if they become curved after the rolling operation they may be straightened by some other operation, and still the process which I set forth will be substantially the same-viz., cutting the blade-blanks from sheet metal of uniform thickness, rolling these blanks between beveled rollers so as to compress the metal in the cutting-edge of the blanks, which will secure the important advantages already set forth.

The-same advantage will also be secured if the blade-blanks are produced from long, straight, flat, and thin bars by cutting said bars transversely into sections of the right length, which may be subsequently curved longitudinally by a suitable operation, and then rolled to produce the straightened and beveled blade,with the same effect as if the bar were originally cut curved from a sheet of steel, as in the preferred method. The preferred method is, however, considered much better and cheaper than any of the modifications suggested.

What Iclaim as my invention is 1. The mode of manufacturing knife-blades, consisting in first cutting the blade-blanks from sheet metal of uniform thickness, then passing the blanks between rollers so as to impart a wedging form to the blank and compress themetal along the cutting-edge of the blade, substantially as herein set forth.

2. The mode of manufacturing knife-blades herein set forth, consisting in first forming the blade-blanks in a longitudinally-curvcd form, thence passing this blank longitudinally between inclined or beveled rollers having a wedging coincidence, so as to reduce the concave edge of the blank, and thereby straighten 

